Temperature-dependent development of the koinobiont endoparasitoidVenturia canescens (Hymenoptera: Ichneumonidae) parasitizingPlodia interpunctella (Lepidoptera: Pyralidae)

Abstract: The effect of various constant temperatures on the growth rate and adult longevity ofVenturia canescens Gravenhorst (Hymenoptera: Ichneumonidae) parasitizing larvae of Plodiainterpunctella Huebner (Lepidoptera: Pyralidae) was studied in the laboratory. Newly parasitizedfifth instar larvae of Plodia interpunctella were transferred to constant conditions of sevendifferent temperature regimes (15, 17.5, 20, 22.5, 25, 27.5, 30°C) and the days needed for theemergence of the parasitoid’s pupa and adult eclosion were measured. Adult longevity was alsostudied under the same conditions. The development of Venturia canescens at 15°C was totallyinhibited. Overall, developmental time decreased significantly with increasing testingtemperature. The shortest developmental time was observed at 27.5°C (20.8 days from parasitismto adult eclosion). Adult longevity was also affected by temperature, as it was significantlyreduced at 27.5°C (8.3 days) and 30°C (9.4 days) compared to that at 20°C (21.7 days) and 25°C(17.8 days). These findings provide us with useful information regarding the potential of using V.canescens as a biological agent in IPM programs.